Here’s my situation; I’ve built a very simple web app that looks up a users location and plots it on a Google map.
Here’s my code: http://pastebin.com/d3a185efd
When I test it, my location is detected as being >= 500 meters from where I actually stand.
BUT
When I open up Google Maps or Gowalla my location is correct to within <20 meters?
So my question is: Do native iPhone apps benefit from a higher accuracy rate than web apps?
If so, why?
According to the specification, webapp geolocation should use whatever positioning method works best in any situation – so in theory, one would assume it uses GPS when available. The discussion linked in the “best answer” by rohit doesn’t seem conclusive to me – here is another one, with someone reporting a similar problem to yours and other users professing to getting accurate gps data (scroll down to comments 26-28 Sept):
http://www.thecssninja.com/javascript/geolocation-iphone
But it does seem like the geolocation stuff is buggy still. I’d suspect your problem is basically that, some bug.